Defoaming and demulsification



DEFOAMING AND DEMULSIFICATION Robert C. Hyatt, Cranford, NJ., and Anthony J. Martinelli, Easton, Pa., assignors to General Aniline 8; Film Corporation, New York, N.Y., a corporation of Delaware No Drawing. Application December 30, 1954 Serial No. 478,873

2 Claims. (Cl. 252-340) This invention relates to the provision of a new process for resolving emulsions of the water-in-oil type and inhibiting foaming of liquid systems.

Various liquid systems exist in industry which are in the form of water-in-oil type emulsions which must be separated into their component parts of oil and water.

Prime examples of suchliquid systems are the petroleum emulsions commonly referred to as cut oil, roily oil, emulsified oil, etc., which are obtained from producing -'wells, pipe lines, from the bottoms of oil storage tanks and the like, and comprise fine droplets of naturally occurring waters or brines dispersed in a more or less permanent state through the oil which constitutes the continuous phase of the emulsion. Water-in-oil type emulsions are also formed under controlled conditions in 'processes for removing impurities, particularly inorganic salts, from pipe line oil. sions encountered in nature or industry include gas tar emulsions, tar sand oil emulsions, emulsions encountered Other water-in-oil type emulin the manufacture of anti-biotic agents, and in the sweetening or caustic washing of hydrocarbons, and the like.

.include emulsions of one liquid in another, suspensions of a solid in a liquid, and the like. 'By way of example,

undesirable foaming may be encountered in the production and/or use of natural or synthetic rubberlatices, rubber latex base paints, plastic latices, dyestufi preparations, pharmaceutical preparations such as penicillin which is made by aerobic fermation, paper pulp in aqueous slurries, glue solutions, drilling muds, materials used in textile finishing operations such as in the application of insoluble finishing compositions, e.g. water-proofing emulsions, and the like.

Both of the problems above described have as a common characteristic an undesirable discontinuous phase. Thus, in the water-in-oil emulsions, the discontinuous water phase must be agglomerated and removed, while in the foaming of various liquid systems, it is the discontinuous air phase in the bubbles of the foam which must be, agglomerated and removed or at least its formation prevented. It is accordingly an object of this invention to provide a process for agglomerating, separating, preventing, and/or inhibiting the formation of such discontinuous phases. Other objects and advantages will appear as the description proceeds.

It has now been found that the aforementioned emulsions and foaming problems may be solved by treatment of the liquid system which contains the water-in-oil emulsion and/ or is subject to foaming with an agent which may be represented by the general formula wherein R is a radical of from 1 to l8 carbon atoms;-

S atent 2 R is a radical of from 1 to 8 carbon atoms; R is selected from the group consisting'of divalent alkyl radicals derived from alkanediols of from 2 to 6 carbon atoms at least 50 mole percent of which are ot,w alkenediols; R is selected from the group consisting of -H, R -OH and and n has a value of about 2 to 15. These agents may be described as at least partially acylated polyesters of dicarboxylic acids and alkanediols.

Such agents may be prepared by' reaction between a dicarboxylic acid of the formula H OOCR -COO-H, an alkanediol of the formula H0R -0H, and a monocarboxylic acid of the formula R -COOH, wherein R R and R have the values given above. The value of n will depend upon the molecular proportions of reactants employed, the reaction conditions, and the stage at which the monocarboxylic acid R COOH is added to the reaction medium. It will be understood, that regardless of the proportions of reactants employed, the polymeric product will not consist of a single material, compound or ester, but of a mixture of polymers of varying chain length and end group composition, combined with small amounts of unreacted monomers and simple esters. In most cases, it is preferred to react the dicarboxylic acid with at least an equimolar amount of the alkanediol in the production of the polyester. In general, proportions of about 1 to 2 moles of alkanediol for each mole of dicarboxylic acid may be employed, whereby the resulting. polymer mixture will contain as its greatest component polyester chains having hydroxy groups at both ends. However, as mentionedabove, it will be apparent that polyester chains'will be present having terminal carboxy groups and/or both a hydroxy and a carboxy terminal' group. The greater the proportion of alkane diol, thegreater the proportion of polyester chains in the product containing two terminals hydroxy groups.

The monocarboxylic acid R --COOH which is employed for partial acylation of the hydroxy containing: polyester chains may be added to the reaction medium at the beginning of the reaction, during the reaction or after the alkanediol and dicarboxylic acid have been re! acted. When added before or during the polyester tonne-- tion, the presence of the monocarboxylic acid in the re action medium will obviously tend to shorten the length of the polyester chains by blocking further reaction of terminal hydroxy groups with carboxy groups of the dicarboxylic acid.

The. reaction for producing the agents operative in instant invention. may be carried out in a manner conventional for esterification procedures at temperatures. ranging fronr' about to 275 0., preferably to 220 C., for a suflicient period of time to complete the: reaction, Durations are generally of from about 2 to 1:2; or 14 hours depending upon whether the monocarboxylic: acid is initially present in the polyesterification medium oris subsequently reacted with the polyester products, the nature and concentration of the reactants, reaction con-- ditions and the like. The use of an inert atmosphere:

such as nitrogen assists in producing an acceptable product of the product. The use of a vacuum in conjunction with:

nitrogen and/or CO as-an inert atrnosphereislikewise beneficial. In this manner all volatile materials, including water vapor and/ or excess alkanediol or the like may be removed by distillation, preferably at a temperature ranging from about 150 to 300 and a pressure-of l mmxof mercury or less for periods of l to 4 hours:

Similar considerations apply to the acylation reaction when the monocarboxylic acid is subsequently added.

Temperatures of about 100 'to 300 C. may be employed operative in the instant invention.

In all cases, at least Suitable dicarboxylic acids which maybe employed for reaction with the alkanediols mentioned above include malonic, succinic, glut-aric, adipic, pimelic, azelaic, sebacic, oxydibutyric, diglycolli'c, phthalic, terephthalic, isophthalic, tetrahydrophthalic acids, and/or mixtures thereof or the like.

It will'be understood from the above that whenever mixtures of alkanediols and/or dicarboxylic acids are reacted together, the polymeric products will contain polyester chains containing varying amounts of the r'eactants. In other words,,in the formulagiven above, the recurringunits in the compound as indicated by the portion in brackets may contain different values for R and R depending upon the reactants employed. However, it has been found that polyesters prepared from adipic acid as the dicarboxylic acid and a mixture of about equimolar amounts of 1,4-butanediol and 1,2-propylene glycol are generally superior in producing the desired results. In the preferred embodiment the polyester is formed from about 3 moles of adipic acid, 2 moles of 1,4- butanediol and 2 moles of 1,2-propylene glycol.

Monocarboxylic acids of from 2 to 19 carbon atoms which may be employed for acylating the hydroxy-chain ended polyesters include acetic, acetic anhydride, acrylic, vinyl acetic, propionic, cyclopropane carboxylic .acid, butyric, 2-ethyl-1-hexanoic, allylacetic, valeric, tiglic, caproic, enanthic, caprylic, pelargonic, angelic, capric, h ldecanoic, oleic, ricinoleic, lauric, erucic, palmitic, margaric, stearolic, stearic, benzoic, mono-Z-ethylhexylphthalate acids or the like. Aliphatic acids of at least 9 carbon atoms are preferred. It will be understood that here also, mixtures of any of these acids may be employed, the resulting products being mixtures of the corresponding acylated polyesters; The proportion of acyl- H ated polyester chains having a terminal hydroxy group will of course be decreased as the 111013.. ratio of acylating monocarboxylic acid to polyester chain is increased. It will be understood that in preparing the agents of this invention, the functional equivalents of the acids may be employed, as for example their anhydrides, halides, salts or the like. Similarly, functional equivalents of the final age'nts such as their salts or the like, may be used in place of the agents per se. a i 7 7 The instant invention may be put into practice for demulsification by simply introducing a relatively small proportion of an agent of the type described above into a relatively large proportion of water-in-oil emulsion, admixing the agent and emulsion with agitation in any of the various types of apparatus now generally used to resolve or break petroleum emulsions with a chemical re agent, preferably with application of heat, and 3,1 9!- in-oil emulsions.

ing the mixture to stand quiescent untilrthe undesirable water content of the emulsion separates and settles from the mass. Slight agitation in the water layer at this point is helpful in breaking webbing that sometimes forms. 'The agent may be added directly or it may be first dissolved in or diluted with any suitable liquid medium to' produce a concentrate or the like. As suitable solvents and diluents there may be mentioned water, petroleum hydrocarbons, benzene, toluene, xylene, aliphatic alcohols such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, octyl alcohol, mixtures thereof, and the like. Said agent may be employed as the sole demulsifier or it maybe employed in admixture with other suitable well known types of demulsifying agents. The solubility of the agent in the oil or water of the emulsion to be treated is not particularly important in view of the very small amounts employed. Thus, concentrations of agent of the order of from about 10 to 100 parts per million (p.p.rn.) in the emulsion, by volume, are usually sufiicient although concentrations outside of this range may in some cases be effective and economically feasible.

Theexamples in the following tables are illustrative of the instant invention and are not to be regarded as limitative.

The examples in Table 1 below illustrate various agents of the type above described, tested and found operative to a greater or lesser degree for demulsification of water- In these demulsification tests, 1.0 ml. and 0.5 ml. of a 1 percent solution of the agent in a solvent mixture of parts by weight of xylene and 50 partsby weight of the isopropyl alcohol were added to .100 ml. of the crude oil emulsion (e.g. Hastings, Skyrock Lease Well #3, Aquaness Co.) in 2. 4-ounce round bottle. The admixtures, in capped bottles were shakcn'for 15 minutes ona mechanical shaker. After removal, the bottles were allowed to stand quiescent for 15 minutes. Color of sample and any separation or water-drop were noted and the bottles then immersed in a water bath at C. for 10 minutes. Water separation was noted, the bottles returned to the mechanical shaker for another 10 minutes, removed and allowed to stand quiescent for another 15 minutes. Color and water-drop (water separation) were noted and the bottles then slightly agitated by swirling the contents to break'the Webbing that forms in a water layer.

TABLE I Demulsification Tests Example [1.33 moles of 1,4-butanediol. 1.33 moles of 1,2-propylene glycol. 2.0 moles of adipic acid.

0.5 moles of Nee-Fat 11.

1.33 moles of 1,4-butanediol.

1.33 moles of 1,2-propylene glycol. 2.0 moles of adipic acid. 0.5 moles of DD coconut fatty acids. 1.33 moles of lA-butanediol.

1.33 moles of 1,2-propylene glycol. 20 moles of adipic acid.

0.4 moles of DD coconut fatty acids. 0.1 moles of benzoic acid.

1.33 moles of 1,2-propylene glycol. 1.33 moles of 1,4-butanediol.

2.0 moles of adipic acid.

0.4 moles of Nco-Fat 11.

0.1 moles of benzoic acid.

1.33 moles of 1,4-butanediol.

1.33 moles of 1,2-propyl ene glycol.

'5 2.0 moles of adipicacid.

0.4 moles of DD coconut fatty acids. 0.1 moles of oleic acid.

1.33 moles of 1,4-butanediol. 1.33 moles of 1,2:propylene glycol.

6 2.0 moles of adipic acid.

0.4 moles of DD coconut fatty acids. 0.1 moles of Z-ethyl-l-hexanoic acid. 1.33 moles of 1,4-butanediol.

1.33 moles of Liz-propylene glycol. 1.33 moles of adipic acid.

0.67 moles of terephthallc acid. 05 moles of DD coconut fatty acids.

agents are listed in the following Table II from information obtained from Armour and Company.

TABLE II Fractionated Tall Oil Old Name DD Coco Neo Fat 9 or 15 N eo Fat 11 Fatty Acids Neo Fat D-142 New Name Neo Fat 265 Neo Fat 10 Neo Fat 12 Neo Fat 42-06 Caprylic Acid percent-- 8 Oapric Acid.-- 7 Laurie Acid... 0 49 Myristic Acid. 17 Palmltic Acid- 9 Btearlc Acid -d 2 Olelc Acid --d0---- 6 50 Llnoleic Acid do-. 2 40 Llnnlenic A ri do 4 Rosin Add: (in 6 Titre --O-- 22-26 28-33 41-43 17 Iod' e Value 14 1.2 1.0 125 Acid Value max 272 329 282 198 TABLE I.Continued Example Reactants Used in Making the Complex Partially Acylated Esters 1.33 moles of 1,4-butanediol.

1.33 moles of 1,2-propylene glycol.

0 moles of adipic acid.

3 moles 01 DD coconut fatty acids. 2 moles of 2-ethyl-1-hexanoic acid. .33 moles of 1,4-butanediol.

0: moles of DD coconut fatty acids.

EXAMPLE II Adipic acid, 1,4-butanediol and 1,2-propylene glycol in molar proportions of, respectively, 3:2:2 were charged into a 4-necked flask equipped with thermometer, nitrogen inlet, sealed stirrer, and short Vigreaux distilling head connected to a condenser. After purging with nitrogen, the reaction mixture was heated at 150 to 212 C. for 6 hours while removing water by distillation as it was formed. The product was transferred to a still pot equipped with capillary inlet for dry, oxygen-free nitrogen, and heated in vacuo at 200 to 250 C. and mm. of mercury for hour to remove excess propylene glycol and butanediol. After cooling, 0.75 moles of Nee-Fat 11 were added and the mixture heated at 140 to 210 C. for 4% hours and then at 200 to 250 C. and 5 mm. of mercury for 1 hour. A pale yellow viscous liquid was obtained having a molecular weight of about 1400.

Dow 512-0 is a latex containing 45% by weight of styrene-butadiene copolymer. Dow 744-B is a latex containing 50% by weight of vinyl chloride-vinylidene chloride copolymer. Rhoplex-WC-9 is a latex of Rhom and Haas containing 40% by weight of acrylic ester polymer. Compositions of certain monocarboxylic acid acylating wherein R is the hydrocarbon radical of lauric acid, R; is the hydrocarbon radical of adipic acid, R is selected from the group consisting of -H, -R --OH and n has a value of about 2 to 15, and R is a hydrocarbon radical derived from a mixture of alkanedoils at least 50 mole percent of which is 1,4-butanediol and the balance is 1,2-propylene glycol.

2. A process as defined in claim 1 wherein said mixture contains about equimolar amounts of 1,4-butanediol and 1,2-propylene glycol.

References Cited in the file of this patent UNITED STATES PATENTS 2,052,282 DeGroote Aug. 25, 1936 2,214,784 Wayne Sept. 17, 1940 2,514,399 Kirkpatrick et al July 11, 1950 2,562,878 Blair Aug. 7, 1951 2,599,538 Blair June 10, 1952 2,686,766 Silverstein et al. Aug. 17, 1954 

1. A PROCESS FOR BREAKING A WATER-IN OIL EMULSION COMPRISING SUBJECTING THE EMULSION TO THE ACTION OF A MIXTURE OF AGENTS OF THE FORMULA 